Described below is a method for pulse-based ultra wide band communication between at least one transmitting node and at least one receiving node.
The technical field of ultra wide band communication, which is also referred to below as UWB communication (Ultra Wide Band) communication is relevant. UWB technology involves near field radio communication which uses very large frequency ranges with a bandwidth of at least 500 MHz or of at least 20% of the arithmetic mean of lower and upper limit frequency of the frequency band used. To keep interference between UWB communication and other wireless communication systems, such as WLAN for example, as low as possible, the average maximum allowed energy for UWB signals for transmission of the signals is prescribed by regulatory authorities. A variant of UWB systems is currently defined by Standard IEEE 802.15.4a. This standard describes media access for UWB communication systems based on impulse radio technology. The communication involved here is a pulse-based UWB communication in which information is encoded independent of frequency by pulses in the UWB signals.
One of the regulatory requirements in respect of UWB transmission satisfying the maximum allowed energy allows either a data transmission with high pulse rates with low energy per pulse or with low pulse rates with high energy per pulse. Although high data rates can be achieved with high pulse rates, because energy falls away with increasing distance during transmission in air, only short ranges can be covered. The higher pulse energy allowed for transmission with a low pulse rate, although offering greater ranges, only provides them at lower data rates.
Currently pulse-based UWB systems with a fixed pulse rate are used. These allow either fast data transmission over short distances or slow data transmission with a long range. In such cases the problem arises that with a number of transmitting and receiving nodes which split the transmission medium, high-bit-rate UWB communication cannot be operated at the same time as low-bit-rate UWB communication. In particular the high pulse energy of the low-bit-rate UWB transmission disrupts high-bit-rate data transmission over a relatively wide area and collisions between the two data transmissions in the jointly-used frequency band result.